Find the mean and variance for the following frequency distribution.

Mean, $\frac{-}{x}=\mathrm{A}+\frac{\sum_{i=1}^{5} \mathrm{f}_{i} \mathrm{y}_{i}}{\mathrm{~N}} \times \mathrm{h}=25+\frac{10}{50} \times 10=25+2=27$

Variance $\left(\sigma^{2}\right)=\frac{h^{2}}{N^{2}}\left[N \sum_{i=1}^{5} f_{i} y_{i}^{2}-\left(\sum_{i=1}^{5} f_{i} y_{i}\right)^{2}\right]$

$=\frac{(10)^{2}}{(50)^{2}}\left[50 \times 68-(10)^{2}\right]$

$=\frac{1}{25}[3400-100]=\frac{3300}{25}$

$=132$